USN-7954-2: Libtasn1 vulnerabilities

Publication date

10 February 2026

Overview

Several security issues were fixed in Libtasn1.


Packages

Details

USN-7954-1 fixed vulnerabilities in Libtasn1. This update provides the
corresponding updates for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu
18.04 LTS, and Ubuntu 20.04 LTS. CVE-2021-46848 only affected Ubuntu
14.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS.

Original advisory details:

It was discovered that Libtasn1 incorrectly handled decoding ASN.1
content. An attacker could possibly use this issue to cause Libtasn1 to
crash, resulting in a denial of service. (CVE-2025-13151)

It was discovered that Libtasn1 incorrectly handled encoding ASN.1
content. An attacker could possibly use this issue to cause Libtasn1 to
crash, resulting in a denial of service. This issue only affected
Ubuntu 22.04 LTS. (CVE-2021-46848)

USN-7954-1 fixed vulnerabilities in Libtasn1. This update provides the
corresponding updates for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu
18.04 LTS, and Ubuntu 20.04 LTS. CVE-2021-46848 only affected Ubuntu
14.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS.

Original advisory details:

It was discovered that Libtasn1 incorrectly handled decoding ASN.1
content. An attacker could possibly use this issue to cause Libtasn1 to
crash, resulting in a denial of service. (CVE-2025-13151)

It was discovered that Libtasn1 incorrectly handled encoding ASN.1
content. An attacker could possibly use this issue to cause Libtasn1 to
crash, resulting in a denial of service. This issue only affected
Ubuntu 22.04 LTS. (CVE-2021-46848)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
20.04 LTS focal libtasn1-6 –  4.16.0-2ubuntu0.1+esm1  
18.04 LTS bionic libtasn1-6 –  4.13-2ubuntu0.1~esm1  
16.04 LTS xenial libtasn1-6 –  4.7-3ubuntu0.16.04.3+esm4  
14.04 LTS trusty libtasn1-6 –  3.4-3ubuntu0.6+esm1  

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